Valve-tappet



F. H. BELLMORE.

VALVE TAPPET..

APPLxcATIoN FILED JAN. 12. 1921.

1,401,234. Patented Dec. 27, 1921.

l/V VEN 70H v ATTORNEYS UNITED STATES PATENT *oi-*Fica vFRED-ERIGK IH.' BELLMORE, 10F NEW BEDFORD, MASSACHUSETTS.

VALVE-TAPPET.

Specicatonof Letters Patent. Patent-(5d Dec, 27 1921 Application led January 12, 1921. Serial No. 436,843.l i

lowing is a specification.

My present invention relates generally to valve tappets, and more particularly to that type of `valve -tappct which includes a cylindrical rbody having a'lower annularly flanged cam engaging end and into whose upper slightly reduced endy an adjusting screw works and is controlled by a lock nut. This v is substantially the type of tappet utilized in connection with detachable head motors and is opento practically but one objection and that'is the noisy action of the parts unless a very tine accurate adjustment of the adjusting screw is maintained at all times. This adjustment is usually effected with the parts cold or practically so by adjusting the nut with a piece of ordinary paper between the same and the lower end ofthe valve-stem which the tappetis adapted to actuate, so as tothus allow for natural expansion when the parts are heated in action,lotherwise the valve would not be permitted to seat properly.

It is the object of my invention to provide means whereby to eliminate this noise with the slightest possible change in construction, and at the Sametime provide for more thorough lubrication of the tappet without danger of overlubrication and waste of oil.

In carrying out my invention lfl provide a tappet whose construction so slightly diiers from that of the ordinary tappet that with its' parts pressed together its external appearance is precisely the same as that of the usual tappet although my invention proposes its manufacture 'in two parts instead of the usual single part and provides for a coaction between these parts in such a way that in use the adjusting screw and the lower flange will snugly engage respectivelyv with the valve stem and cam at all times.

In the accompanying drawing which illustrates my present invention and forms a part .of this specification,

Figure 1 is a sectional side view illustrating the practical application of my invention,

Fig. 2 is a detail side view partly broken away and in section'ot the lower portion ofthe tappet,

Fig. 3 is a top plan view thereof,

Fig. 4 is aside view and in section of the upper part of' the itappet7 and Fig. 5*.is a top plan view ot the parts shown in Fig. 4.

Referring now tothese figures and particularly to Fig. l it will be notedthat the valve tappet, generally indicated at 10, works through a bearing 1l, its lower flanged rend. 12 depending into the crank case and into engagement with its respective cam 13 of the cam shaft 1li. The npperend of the tappet 10 has an axial threaded bore receiving an adjusting nut 15 and is slightly partly broken away reduced as at 16 to facilitate engagement of a wrench and the like with'the lock .nut 17 which threads on the screw 15 and in its effective position abuts and tightly engages the upper end of the tappet to lock the adj usting screw in position. i

Ordinarily with theparts cold. or substantialiy so the adjusting screw 15must be slightlyspaced r'rom the lower end of the respective valve stem 18 when the valve at the upper'end of this stem (not shown) is rfully seated under tension of the valve spring 19, in order that when the parts become heated,ythere will be suilicient room for the valve stem to j expand and vstill permit tull,V proper and ,even seating of the valve. Unless this adjustment is ycarefully and properly made it is obvious thereis considerable danger 'of free endwise play of the tappet and this is particularly true after slight wear has taken place, which results in 'a noisy valve' action4 thatV my invention seeks to overcome.

In carrying out my invention, the tappet is divided into two parts at a peint approximately midway between its ends, the lower 24 is seated as in Fig. 1 and from which this coil spring partially projects for engage-V ment with thelower closed end of the lower part 2O.V Moreover the lower part 20 has radial oil openings through its wall irnmediately above its flange 127 through which v oil from the crank case .-ndsits way into the bore of the cylindrical part 20, oil also finding its way upwardly on the external surface of this cylindrical part 20 to: the space between its upper end and the annular shoulder 26 of the upper part 22 so as to thus form an oil cushion between the abutting portions of the two parts of the tappeti both on the Vupper end 'of the lower part 2O Y and the lower end of the extension 21 of the part 22,` Y c y It isquite obvious from the foregoing that when the two parts 2O and 21 are pressed lengthwise into closely contacting relation against'the compression of spring 2li, lthe tappetpresents the same external appearance of the ordinary tappet, is capable of working inthe same bearing7 and is thus adaptable for use without changing Aany ofthe surrounding ordinary parts ofi the motor in connection with which 1t is to i` shift the two parts ofthe tappet awayV from one another in order to maintain the adjusting screw 15 and the flange 12 in even uni form contact respectively withn the valve stem 1S and the cam 13. A

, In adjusting the tappet its parts are pressed tightly together and the adjustment before described as to the 'adjusting screw 15 is elfected. Instantly uponrclease of the tappet its partsvv expand lengthwise under tension'of spring 2e and the uniform engagement above described with the parts between which the tappet is disposed is maintained from this time on. Oil iinding its way upwardly upon the external surface of the cylindrical part 20 constantly maintains anoil cushion as previously described between the upper end of this part and the shoulder'26 ofthe upper part, and similarly oil entering the openings 25 maintains an effective oil cushion at the lowerend of the extension 21 so as to prevent noise in use .the usual tappet VtheV cylindrical bodyv of which presents asmooth surface from end to end. 7

I claim:

1. A valve tappet having a body presenting a smooth external surface of one diameter throughout, formed in, two partsthe lower part of which is cylindrical and has a lower closed and flanged cani'engaging end and the upper part of which has'an upper adju-sting screw and al reduced depending extension which slidably interts the lhollow lower part and forms a shoulderopposing the up,- per end of the lower part, and a spring carried between the lower end of said extension Y and the closed base of the hollow part Vwhereby to `place the parts undercompression 1n use7 said lower hollow part having `an oil intake opening' laterally through its wall immediately above itsy flanged lower end to freely receive oil below the lower end of the extension of the upper part; A v

2. A valve tappet comprising a lower cy-k lindrical part having a lower closed end and a iange surrounding said end, an upper part having a reduced lower stemrslidablyinterfitting the bore of said lower part and foirning an annular shoulder opposing the upper end of the lower part, said upper part having an adjusting screw at its upper end y and an axial borein its loweiend7 and a spring within the bore bearing against the lowervclosed end of the lower part7 said upper and lower parts being ofthe saine diameter and' said lower part having an aperture through its wall opening into its bore above the flange and below the lower end` of the upper art as described. Y

YFR DERCK BELLMORE l 

